RecruitingClinical trialPassive Heat Therapy for Lowering Systolic Blood Pressure and Improving Vascular Function in Mid-life and Older AdultsThis study aims to determine the effects of \~12 weeks of repeated hot water immersion ("heat therapy") vs. thermoneutral water immersion on blood pressure and vascular function in late middle-life to older (≥40 years) adults. The study also aims to determine the effects of \~12 weeks of heat therapy on fluid cognitive and cerebrovascular function.